The return of LPG

By ALASTAIR SLOANE

Ford New Zealand and Rockgas, the country's largest supplier of liquid petroleum gas, are about to promote LPG as an alternative to increasingly expensive petrol.

Not since the 1970s and 1980s - when New Zealanders were using about 90,000 tonnes of LPG a year, mostly in dual-fuel vehicles - has the gas been given such support.

Rockgas is using public relations company the Sigma Group to get the message across.

The LPG campaign comes as the price of a litre of petrol goes beyond $1.10. Unleaded 91 in downtown Auckland yesterday was $1.11 and premium 96 unleaded $1.14. At the same petrol station, a litre of LPG cost 64c.

Rockgas is getting in behind Ford and its new LPG model Falcons, one an LPG-only unit and the other dual-fuel. The gas-only Falcon costs $42,000 and the gas/petrol model $43,500.

The growth of LPG and CNG as alternative fuels started in the late 70s and went on through the 80s as New Zealanders, faced with the increasing petrol cost, , converted their vehicles to run - at the switch of a button - on petrol or gas.

But interest in LPG and CNG fell at the end of the 80s as petrol became cheaper. The downturn meant that industries which had invested in dual-fuel conversion equipment had to sell much of it overseas, often at a loss.

There has been renewed interest in alternative fuels since the price of petrol began going up a few months ago, particularly in Australia where Ford services thousands of LPG-powered taxis. Investment there is such that a 60,000-tonne LPG storage tank opened last week near Sydney airport.

Ford New Zealand is getting in behind its dedicated, factory-built LPG Falcon Forte, despite there being fewer LPG outlets than petrol pumps.

Ford says the LPG Falcon is more environmentally friendly - emitting about 30 per cent fewer pollutants - and cheaper to run than a petrol car.

LPG is a blend of propane and butane. The more propane the higher the octane rating of LPG. At a mix of 85 per cent propane and 15 per cent butane, LPG rates at 92 octane.

LPG is not as energy-rich as petrol, however, although engine torque in the Falcon Forte is up marginally over the petrol motor.

Fuel consumption in the LPG Falcon is also up, returning about 15 litres for every 100km in the city and 9 litres for every 100km in the country.

But Ford says the cruising range of the LPG Falcon, with a 92-litre tank in the sedan and 110 litres in the stationwagon, is greater than that of the standard Falcon with its 4-litre six-cylinder petrol engine.

The LPG model doesn't have a petrol tank. Instead, twin steel tanks are mounted under a specially designed flat boot floor, unlike conversions of years ago where much of the boot was occupied by a gas cylinder. The Falcon's engine has been modified for LPG use.

Ford is using extra-hard valve seats for the hot-burning fuel and a special throttle system. It says engine durability with LPG-only won't be a problem - it has already tested it to 250,000km.